A cloth used in side cloths of down wears or futons is required to have a low air permeability in order to restrain cotton or down from spouting out. The cloth is also required to be light and thin.
In the past, for the cloth, a natural fiber, such as silk or cotton, which is excellent in feeling or comfortableness, has been used. However, the cloth made of natural fibers are small in tear strength and poor in durability; thus, when the cloth is used, in particular, for a down wear, there is caused a problem that cotton or down spouts from an elbow or a sleeve portion thereof.
In contrast, the fabrics made of a polyester multifilament, a nylon multifilament or a composite synthetic fiber of these filaments have also been frequently used for the above-mentioned cloth since mechanical properties thereof are excellent. These fabrics are frequently used for coats, blousons, golf wears, outdoor wears for sports, and other wears since these fabrics are soft, light, and excellent in windproofness, water repellency, strength and others. However, the fabrics are required to have a dense structure in order to keep down proof for restraining down from spouting out from the fabrics. Thus, there arises a problem that the fabrics become hard. In order to solve this problem, for example, various fabrics are suggested to make improvements, as disclosed in Patent Documents 1 to 3.
<High-Density Fabric Using Microfiber>
Patent Document 1 discloses a side cloth for a futon wherein use is made of a spun yarn or long fiber yarn comprising monofilaments having an average fineness of 0.5 denier or less. This side cloth is a high-quality side cloth for a futon, which causes no cotton to spout from the cloth and has a soft feeling, a rich drapability, and a good gloss. Although the feeling of the side cloth is soft since the fineness of the monofilaments thereof is small, the number of the filaments that constitutes the yarn is large so that the yarn becomes thick. As a result, the cloth becomes thick. Thus, the side cloth is not a cloth having lightness, thinness, and down proof.
<Thin High-Density Fabric Using Multifilaments Having Small Total Fineness>
Patent Document 2 suggests a polyester fabric which has a total cover factor of 1500 or more and a weight per unit area of 45 g/m2 or less, which comprises a polyester multifilament A yarn ha ring a total fineness of 25 dtex or less and a monofilament fineness of 2.0 dtex or less, and a multifilament B yarn having a total fineness of 35 dtex or more, in which in a yarn-arrangement in each of warp and weft directions the constituent-filament-ratio (ratio by filament number) of the B yarn to the A yarn is from ¼ to 1/20, and the pitch between the A yarn and the B yarn is 7 mm or less. Polyester multifilaments far finer than conventional multifilaments is used for this polyester fabric, and the fabric is lighter, higher in density; and softer, while a sufficient tear strength is exhibited. Although the fabric is soft since the far finer polyester multifilaments are used therein, it is necessary for heightening the strength of the fabric to use the B yarn, which has a large fineness of 35 dtex or more. Further, the fabric has a problem that the constituent-filament-ratio of the A yarn to the B yarn is restricted.
<High-Density Fabric Using Microfiber & Textured Yarn>
Patent Document 3 discloses a high-density fabric wherein use is made of a polyester long fiber yarn having a monofilament fineness of 0.6 denier or less and a total fineness of 60 to 120 deniers, wherein warps are made of crimped yarn, and the total fineness (WD) of the warps, the total fineness (FD) of wefts, and the cover factor (WCF) of the warp are each regulated into a specified range. This high-density fabric is a fabric that has a high waterproofing property, is well-tailored after the fabric is sewed up, further has a tear strength the level of which does not cause any practical problem, and is soft. However in order to prevent the fabric from slant upward even when the yarn constituting the fabric is curved with a sewing needle at the time of sewing this fabric, a false twist textured yarn having a large fineness of 60 deniers or more is used. For this reason, the high-density fabric with lightness and thinness, softness and further having an excellent down proof cannot be obtained.